Kazuhide Kanenishi & Kenji Matsuura, Center for Advanced information Technology, The University of Tokushima, Japan; Takahiro Oie & Yasuo Miyoshi, Institute of Technology and Science, The University of Tokushima, Japan; Masahiko Sano, Center for Advanced information Technology, The University of Tokushima, Japan; Yone Yano, Institute of Technology and Science, The University of Tokushima, Japan